1. Field of the Invention
The present invention relates to a wall electrode-type liquid crystal display device, and particularly to a liquid crystal display device in which the display performance and reliability are improved.
2. Description of the Related Art
Liquid crystal display devices have been used in a wide range from small-sized mobile terminals to large-sized televisions due to the characteristics such as the high quality of display, a small thickness and a light weight, and low power consumption.
On the other hand, viewing angle characteristics are important in liquid crystal display devices, and IPS (In-plane Switching)-type liquid crystal display devices have been proposed to realize a wide viewing angle. In the IPS type, while liquid crystal molecules are horizontally directed, electric field in parallel with the substrate is applied to rotate the liquid crystal molecules in a horizontal plane, so that the amount of backlight can be controlled to display an image.
Japanese Patent Application Laid-Open Publication No. H6-214244 discloses a liquid crystal display device having a predetermined structure in which m×n pieces of pixels in a matrix shape, active elements in the pixels, driving means to apply a predetermined voltage waveform, and a pair of electrodes that keeps constant a gap between upper and lower substrates in the pixel are provided, and the alignment state of liquid crystal molecules can be controlled to modulate light by applying electric field in parallel with the surface of the substrate to between the pair of electrodes (see Abstract).